{"id":"ALPINE-CVE-2021-26933","details":"An issue was discovered in Xen 4.9 through 4.14.x. On Arm, a guest is allowed to control whether memory accesses are bypassing the cache. This means that Xen needs to ensure that all writes (such as the ones during scrubbing) have reached the memory before handing over the page to a guest. Unfortunately, the operation to clean the cache is happening before checking if the page was scrubbed. Therefore there is no guarantee when all the writes will reach the memory.","modified":"2026-08-27T22:18:01.547478860Z","published":"2021-02-17T02:15:13.097Z","upstream":["CVE-2021-26933"],"references":[{"type":"ADVISORY","url":"https://security.alpinelinux.org/vuln/CVE-2021-26933"}],"affected":[{"package":{"name":"xen","ecosystem":"Alpine:v3.11","purl":"pkg:apk/alpine/xen?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.9.0"},{"fixed":"4.13.2-r5"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-26933.json"}},{"package":{"name":"xen","ecosystem":"Alpine:v3.12","purl":"pkg:apk/alpine/xen?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.9.0"},{"fixed":"4.13.2-r5"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-26933.json"}},{"package":{"name":"xen","ecosystem":"Alpine:v3.13","purl":"pkg:apk/alpine/xen?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.9.0"},{"fixed":"4.14.1-r2"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-26933.json"}},{"package":{"name":"xen","ecosystem":"Alpine:v3.14","purl":"pkg:apk/alpine/xen?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.9.0"},{"fixed":"4.14.1-r3"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-26933.json"}},{"package":{"name":"xen","ecosystem":"Alpine:v3.15","purl":"pkg:apk/alpine/xen?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.9.0"},{"fixed":"4.14.1-r3"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-26933.json"}},{"package":{"name":"xen","ecosystem":"Alpine:v3.16","purl":"pkg:apk/alpine/xen?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.9.0"},{"fixed":"4.14.1-r3"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-26933.json"}},{"package":{"name":"xen","ecosystem":"Alpine:v3.17","purl":"pkg:apk/alpine/xen?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.9.0"},{"fixed":"4.14.1-r3"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-26933.json"}},{"package":{"name":"xen","ecosystem":"Alpine:v3.18","purl":"pkg:apk/alpine/xen?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.9.0"},{"fixed":"4.14.1-r3"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-26933.json"}},{"package":{"name":"xen","ecosystem":"Alpine:v3.19","purl":"pkg:apk/alpine/xen?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.9.0"},{"fixed":"4.14.1-r3"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-26933.json"}},{"package":{"name":"xen","ecosystem":"Alpine:v3.20","purl":"pkg:apk/alpine/xen?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.9.0"},{"fixed":"4.14.1-r3"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-26933.json"}},{"package":{"name":"xen","ecosystem":"Alpine:v3.21","purl":"pkg:apk/alpine/xen?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.9.0"},{"fixed":"4.14.1-r3"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-26933.json"}},{"package":{"name":"xen","ecosystem":"Alpine:v3.22","purl":"pkg:apk/alpine/xen?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.9.0"},{"fixed":"4.14.1-r3"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-26933.json"}},{"package":{"name":"xen","ecosystem":"Alpine:v3.23","purl":"pkg:apk/alpine/xen?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.9.0"},{"fixed":"4.14.1-r3"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-26933.json"}},{"package":{"name":"xen","ecosystem":"Alpine:v3.24","purl":"pkg:apk/alpine/xen?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.9.0"},{"fixed":"4.14.1-r3"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2021-26933.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N"}]}